Mrs L, a work of literary journalism, and exegesis: The poetics of literary journalism and illuminating absent voices in memoir and biography.

Was Henry Lawson’s decline into alcoholism, poverty and an early death really caused by his wife, Bertha Lawson? The biographers of the iconic bush poet and writer – most notably Denton Prout (1963), Manning Clark (1978) and Colin Roderick (1991) – have all constructed a victim as hero narrative around Lawson’s life, blaming Bertha Lawson (nee Bredt) for his personal and creative decline. With these biographies in mind, the thesis Mrs L is a work of literary journalism that is an alternative reading of Bertha Lawson as a single parent with two young children and a limited ability within the mores of the time to provide for her family. Mrs L repositions Bertha within a post separation and divorce single motherhood discourse that was emerging alongside suffragette narratives in Australia at the turn of the 20th century. In doing so, it illuminates her voice, one that has been absent in previous biographies of Henry Lawson. Mrs L further intertwines a contemporary memoir of single parenting that reflects upon the historic narrative to conclude that there remain many similarities in the experience of separation and divorce for women despite considerable changes in law across the century. The accompanying exegesis reflects upon the thesis Mrs L as a hybrid text of biography and memoir described by Sidonie Smith and Julia Watson (2001) as the auto / biography or a / b genre. The exegesis explores the distinctions and relationships between literary journalism, memoir and biography, and suggests literary journalism as a poetics methodology (Lasky, 2013; Sims, 1995, 2012) for writing a / b texts such as Mrs L. Additionally, the exegesis posits that an epistolary strategy can replace the literary journalism technique of immersion in historical works such as Mrs L and the collective biography (Caine, 2010) The Forgotten Rebels of Eureka (Wright, 2013). Responding to a recent critique by David Marr (2016-2017) of the use of first person in biographies, the exegesis further considers the role of the cultural self in memoir (Grant, 2016; Larson, 2007), its place in the a / b genre, and how the “biography as corrective” (Hamilton, 2016, p. 15) is encouraging revisionist as well as innovative explorations of biographical subjects whose voices have been negated in the past

Factors affecting the detection of Clostridium difficile in faecal samples

Clostridium difficile infection (CDI) laboratory diagnostic assays have variable performance, but reasons behind this variability are not well defined. In contrast to previous findings, the PCR ribotype of the organism only appears to be a factor in reduced sensitivity for toxin enzyme immunoassays (EIAs), not glutamate dehydrogenase (GDH) EIAs. Growth curve data demonstrated that GDH is produced during the exponential phase of growth, and the sensitivity of the GDH assay in vivo may be related to the amount of protein produced by the organism, as very high levels of GDH were detected during growth of C. difficile in an in vitro gut model. Indeed the levels of GDH, measured in both gut model and patient samples, correlated with organism bioload. In addition, the median faecal levels of GDH in recurrent CDI cases were significantly higher than in patients with a single infection episode. Interestingly, when patients had sequential faecal samples tested, 27% with an initial GDH-positive/toxin-negative result had a subsequent toxin positive sample, after a median of eight days. Further studies, with supplementary assays for gut inflammation, are required, to determine if these are ‘missed’ infections or insignificant sub-clinical levels of toxin. A laboratory test that could predict risk of recurrence would be an important tool to inform choice of appropriate C. difficile treatment and prevention options. Indeed GDH detection may offer such an opportunity; a cohort of patients has been identified who were consistently GDH positive, even after resolution of symptoms, who subsequently developed recurrent CDI following additional antimicrobial therapy. The cycle threshold (CT) value of PCR assays for the detection of toxin gene may also provide additional information, as low CT (<25) was significantly associated with toxin positivity, presence of PCR ribotype 027 and mortality. Low CT was also associated with recurrence but was not a significant finding

Substance P selectively decreases paired pulse depression in the rat hippocampal slice

BACKGROUND: Although being widespread in the hippocampus, the role tachykinins play in synaptic transmission is unclear. The effect of substance P on field potentials evoked by stimulation of the Schaffer collateral-commissural fibres and recorded from the CA1 region of the rat hippocampal slice were studied. RESULTS: Perfusion of substance P (8 μM) had no effect on the fEPSP or population spike. Substance P did however cause a selective reduction in the paired pulse depression of population spikes evoked by paired stimulation at interpulse intervals of 20–80 msec. A comparison of the actions of other tachykinin receptor agonists gave an order of potency of substance P > [β-Ala(8)]-neurokinin A (4–10) > senktide. The effect of substance P was reduced by the neurokinin-1 receptor antagonist SR140333, but not by the neurokinin-2 or neurokinin-3 receptor antagonists, MDL 29,913 or [Trp(7), β-Ala(8)]-neurokinin A (4–10). CONCLUSION: The order of potency of the agonists, and the effects of the antagonists, both indicate that the effect of substance P on paired pulse depression is mediated by neurokinin-1 receptors

Efficiency of respirator filter media against diesel particulate matter: a comparison study using two diesel particulate sources

Diesel engines have been a mainstay within many industries since the early 1900s. Exposure to diesel particulate matter (DPM) is a major issue in many industrial workplaces given the potential for serious health impacts to exposed workers; including the potential for lung cancer and adverse irritant and cardiovascular effects. Personal respiratory protective devices are an accepted safety measure to mitigate worker exposure against the potentially damaging health impacts of DPM. To be protective, they need to act as effective filters against carbon and other particulates. In Australia, the filtering efficiency of respiratory protective devices is determined by challenging test filter media with aerosolised sodium chloride to determine penetration at designated flow rates. The methodology outlined in AS/NZS1716 (Standards Australia International Ltd and Standards New Zealand 2012. Respiratory protective devices. Sydney/Wellington: SAI Global Limited/Standards New Zealand) does not account for the differences between characteristics of workplace contaminants like DPM and sodium chloride such as structure, composition, and particle size. This study examined filtering efficiency for three commonly used AS/NZS certified respirator filter models, challenging them with two types of diesel emissions; those from a diesel generator and a diesel engine. Penetration through the filter media of elemental carbon (EC), total carbon (TC), and total suspended particulate (TSP) was calculated. Results indicate that filtering efficiency assumed by P2 certification in Australia was achieved for two of the three respirator models for DPM generated using the small diesel generator, whilst when the larger diesel engine was used, filtering efficiency requirements were met for all three filter models. These results suggest that the testing methodology specified for certification of personal respiratory protective devices by Standards Australia may not ensure adequate protection for respirator users against DPM under all circumstances of diesel generated particles

Are respiratory protection standards protecting worker health against ultrafine diesel particulate matter emissions? An Australian perspective

Poster presentation made at the 20th ETH-Conference on Combustion Generated Nanoparticles, 13-16 June 2016, Zurich, Switzerland. Aim: Ultrafine diesel engine emissions are known to cause adverse health impacts including lung cancer, cardiovascular and irritant effects (World Health Organisation 2012). Respiratory protective devices are commonly used to mitigate worker exposure to many hazardous contaminants, especially in heavy industry such as mining and refining. Current standards to evaluate penetration through respirator filter media may not consider ultrafine particles due to the diameter of the challenge aerosol and the detection limit of the instrument (Eninger et al. 2008). Nor do they test penetration at flow rates representative of moderate to heavy work rates. Research is currently being undertaken at the University of Wollongong, Australia, to develop a method to measure penetration through respirator filter media using diesel emissions, rather than the standard challenge aerosol of NaCl, at flow rates consistent with moderate to heavy work rates. Methods: Emissions from a Detroit D706 LTE diesel engine were fed into an experimental chamber which was purpose built for the study. Penetration through a range of commonly used respirator filters in Australian workplaces was determined by particle count at diameters ranging from 5.6 - 560nm, using an Engine Emissions Particle Sizer (EEPS). Penetration was also measured by mass of Elemental Carbon, using NIOSH 5040. Flow rates were as designated in AS/NZS 1716 (Standards Australia International Ltd & Standards New Zealand 2012) and ISO DIS 16975 - 1.2 Work Rates 2 and 3 (ISO 2015), consistent with moderate to heavy work rates. Results and Conclusions: A method has been developed and validated and a pilot study completed. Initial findings indicate penetration exceeded standards specified limits for filtering efficiency for a number of filters for the size range \u3c50 \u3enm, when measured as a function of particle count. Penetration through the filters was found to increase as flow rate increases. These results differed from the penetration by mass of elemental carbon through the respirator filters, using a paired samples t-test at a significance level of 0.05. This research is relevant as it has been postulated that ultrafine particles may contribute to adverse cardiovascular mortality and morbidity associated with diesel engine emissions (Martinelli, Olivieri & Girelli 2013) hence it is important to determine if these smaller size particles are penetrating through respirator filter media and may be inhaled by workers

Reverse taxonomy for elucidating diversity of insect-associated nematodes: a case study with termites

BACKGROUND: The molecular operational taxonomic unit(MOTU)has recently been applied to microbial and microscopic animal biodiversity surveys. However, in many cases, some of the MOTUs cannot be definitively tied to any of the taxonomic groups in current databases. To surmount these limitations, the concept of "reverse taxonomy" has been proposed, i.e. to primarily list the MOTUs with morphological information, and then identify and/or describe them at genus/species level using subsamples or by re-isolating the target organisms. Nevertheless, the application of "reverse taxonomy" has not been sufficiently evaluated. Therefore, the practical applicability of "reverse taxonomy" is tested using termite-associated nematodes as a model system for phoretic/parasitic organisms which have high habitat specificity and a potential handle (their termite host species) for re-isolation attempts. METHODOLOGY: Forty-eight species (from 298 colonies) of termites collected from the American tropics and subtropics were examined for their nematode associates using the reverse taxonomy method and culturing attempts (morphological identification and further sequencing efforts). The survey yielded 51 sequence types (= MOTUs) belonging to 19 tentatively identified genera. Within these, four were identified based on molecular data with preliminary morphological observation, and an additional seven were identified or characterized from successful culturing, leaving eight genera unidentified. CONCLUSIONS: That 1/3 of the genera were not successfully identified suggests deficiencies in the depth of available sequences in the database and biological characters, i.e. usually isolated as phoretic/parasitic stages which are not available for morphological identification, and too many undiscovered lineages of nematodes. Although there still is the issue of culturability of nematodes, culturing attempts could help to make reverse taxonomy methods more effective. However, expansion of the database, i.e., production of more DNA barcodes tied to biological information by finding and characterizing additional new and known lineages, is necessary for analyzing functional diversity.Natsumi Kanzaki, Robin M. Giblin-Davis, Rudolf H. Scheffrahn, Hisatomo Taki, Alejandro Esquivel, Kerrie A. Davies and E. Allen Herr

A pyridinium derivative from Red Sea soft corals inhibited voltage-activated potassium conductances and increased excitability of rat cultured sensory neurones

BACKGROUND: Whole cell patch clamp recording and intracellular Ca(2+ )imaging were carried out on rat cultured dorsal root ganglion (DRG) neurones to characterize the actions of crude extracts and purified samples from Red Sea soft corals. The aim of the project was to identify compounds that would alter the excitability of DRG neurones. RESULTS: Crude extracts of Sarcophyton glaucum and Lobophyton crassum attenuated spike frequency adaptation causing DRG neurones to switch from firing single action potentials to multiple firing. The increase in excitability was associated with enhanced KCl-evoked Ca(2+ )influx. The mechanism of action of the natural products in the samples from the soft corals involved inhibition of voltage-activated K(+ )currents. An active component of the crude marine samples was identified as 3-carboxy-1-methyl pyridinium (trigonelline). Application of synthetic 3-carboxy-1-methyl pyridinium at high concentration (0.1 mM) also induced multiple firing and reduced voltage-activated K(+ )current. The changes in excitability of DRG neurones induced by 3-carboxy-1-methyl pyridinium suggest that this compound contributes to the bioactivity produced by the crude extracts from two soft corals. CONCLUSION: Sarcophyton glaucum and Lobophyton crassum contain natural products including 3-carboxy-1-methyl pyridinium that increase the excitability of DRG neurones. We speculate that in addition to developmental control and osmoregulation these compounds may contribute to chemical defenses

\u3ci\u3eFicotylus laselvae\u3c/i\u3e n. sp. (Tylenchomorpha: Anguinidae) associated with \u3ci\u3eFicus colubrinae\u3c/i\u3e in Costa Rica

Ficotylus laselvae n. sp. was recovered from under the bracts of figs (syconia) of Ficus colubrinae from La Selva, Costa Rica, during a survey of nematode rainforest biodiversity and is described herein. This is only the second report of an association between the nematode suborder Tylenchina and the sycones of figs. Previous reports of most nematode associates of the sycones of figs have been from the lumen and involved transmission by female fig wasp pollinators (Agaonidae) during pollination/oviposition (e.g., Schistonchus and Parasitodiplogaster spp.). The association between F. laselvae n. sp. and Ficus colubrinae may involve an invertebrate host, but none was recovered from dissections of the bracts during this study. It is also possible that this is a rainforest understory nematode that feeds ectoparasitically in protected areas on the aerial parts of F. colubrinae. Molecular analysis using near-full-length sequences of the small subunit (SSU) rRNA and D2-D3 expansion segments of the large subunit (LSU) rRNA genes of Ficotylus laselvae n. sp. suggests that it is a member of the suborder Tylenchina (infraorder: Tylenchomorpha; family: Anguinidae) and that the closest sequenced species is F. congestae from the lumen of sycones of Ficus congesta from Queensland, Australia. Although both nematode species are associated with figs, they are morphologically divergent, suggesting that the different micro-niches that they fill provide different selective pressures for evolution of differing morphological characters or they represent different life history morphotypes of a dicyclic genus